为预测不同寄主植物上桃蛀螟Conogethes punctiferalis(Guenée)越冬种群的变化,研究了幼虫期取食玉米、高粱和向日葵的桃蛀螟越冬幼虫体内水分和脂肪及血淋巴小分子糖(醇)与抗寒性的关系。与取食高粱和向日葵相比,取食玉米的桃蛀螟幼虫生长发育更好,越冬幼虫体重、脂肪含量显著高于前二者,降低体内含水量时期显著早,12月上旬为74.0%,而前者为82.3%和84.6%,过冷却点显著低。初冬和初春,3种寄主植物上桃蛀螟越冬幼虫的过冷缺点没有显著差异。然而隆冬季节,玉米上越冬幼虫的过冷缺点最低(-17.74℃),其次是高粱(-14.62℃),向日葵的最高(-11.68℃)。这说明,寄主植物对幼虫的生长发育、越冬物质储备及含水量有显著的影响,从而影响了滞育幼虫的抗寒能力。越冬幼虫血淋巴中小分子糖(醇)主要有海藻糖、甘油、肌醇、葡萄糖、山梨醇、半乳糖和甘露糖等。从初冬到隆冬,幼虫体内甘油含量显著上升,提高了15～101.8倍,而葡萄糖的含量变化则相反,越冬幼虫体内甘油含量变化与其抗寒能力的变化一致,说明甘油是越冬幼虫提高抗寒能力的重要物质,而合成甘油需要葡萄糖。 In order to predict the overwintering population of Conogethes punctiferalis (Guenée) in different host plants, the effects of water, fat and hemolymph small molecules of sugar (alcohol) on overwintering larvae of larva of corn borer, sorghum and sunflower Cold-resistant relationship. Compared with the sorghum and sunflower, larvae of corn borer larvae grew better and developed. The body weight and fat content of overwintering larvae were significantly higher than those of the former two groups. The reduction of body water content was earlier and earlier, reaching 74.0% in early December, While the former is 82.3% and 84.6%, the subcooling point is significantly lower. There were no significant differences in overcooling overwintering larvae of three host plants, moth borer, in early winter and early spring. However, in the winter season, overwintering larvae had the lowest over-cooling disadvantage (-17.74 ℃), followed by sorghum (-14.62 ℃) and sunflower (-11.68 ℃). This shows that the host plant larvae growth and development, overwintering material reserves and water content had a significant impact, thus affecting the ability of diapause larvae of cold resistance. Overwintering larvae hemolymph small molecule sugar (alcohol) are mainly trehalose, glycerol, inositol, glucose, sorbitol, galactose and mannose and so on. From early winter to winter, larvae glycerol content increased significantly, increased 15 ~ 101.8 times, while the content of glucose in the contrary, overwintering larvae changes in glycerol content and its resistance to cold changes, indicating that glycerol is overwintering larvae to improve cold resistance Of the important material, and synthetic glycerol need glucose.